Sixty-nine patients requiring a gastrointestinal endoscopic procedure were randomly assigned to receive a TCI effect site (e) of remifentanil (n=30) or propofol (n=39). The primary outcome was patient satisfaction. Secondary outcomes included gastroenterologist satisfaction, the proportion of adverse events between the two groups were compared (occurrence of cardiac arrhythmias, mild respiratory depression, major respiratory depression, bradycardia, hypotension, pain, nausea or vomiting, and lack of amnesia), and the level of consciousness.